The present invention relates to a light modulator and method of manufacture thereof.
In a light modulator, by means of the electrostatic force generated by an electrical potential difference between a micromirror and a drive electrode, the micromirror is tilted, and by means of this light from a light source is modulated. As a light modulator is known, for example, a DMD (Digital Micromirror Device) constituted by a large number of micromirrors disposed in a matrix. By means of a DMD, a large screen with high resolution and high intensity can be provided. For this reason, a DMD is used for a projected image device such as a projector or the like.
A light modulator has a laminated construction comprising a mirror substrate having micromirrors, and an electrode substrate having drive electrodes. The micromirror is driven to tilt about a support (post) provided between the mirror substrate and electrode substrate as fulcrum. The support is fixed to an axis portion (torsion bar) of the mirror substrate when the axis portion couples a plurality of micromirrors together and acts as the axis for tilting.
Since the micromirror is driven to twist between the support and axis portion, stress is concentrated on the boundary of the support and axis portion. Conventionally, since the support and axis portion were formed separately, and subsequently fixed together by an adhesive or the like, when the micromirror was driven to tilt the stress was concentrated, and the boundary was subject to fracture.